AGRIC,  DEPT, 


ENTOMOLOGY 

I  IRPflRY 


SCALE  INSECTS 


ON 


DECIDUOUS  AND  ORNAMENTAL  TREES. 


S.  F.  CHAPIN,  M.  D. 


\\ 


Vice-President  of  State  Board  ,>/'  Horticultural  Commissioners 


A  REPORT  TO  THE  STATE  BOARD  OF  HORTICULTURAL  COMMISSIONERS. 


[Reprinted  for  the- Author  from  the  PACIFIC  Hi  \\\\.  I'KKSS 
of  <K;t.  aSiin.l  Nov.  4,  1882.] 


Pacific  Rural  ''J^ess  P. 
1882. 


it,  Sim  J-rii 


AGRIC.  DEPT. 


s 


SCALE  INSECTS  ON  DECIDUOUS  AND  ORNAMENTAL  TREES. 

By   S     F.    CHAPIN,    M.    D., 

\',«  -/Y<  xitli'n.t  uj  til ai<'..  Hoard  of  Horticultural  Commissioner 8. 


A  Report  to  the  State  Board  of  Horticultural  Commissioners. 


^Reprinted  for  the  Aiithor  from  the  PACIFIC  RURAL  PRESS  of  Oct.  28  and  Nov.  4,  1882.] 


The  prevalence  of  scale  insects  in  the  or- 
chards of  Santa  Clara  valley  during  the  past 
few  years  has  afforded  ample  scope  for  their 
study,  to  which  I  have,  for  the  past  three  sea- 
sons, devoted  what  time  I  could  command. 
Assigned  to  this  work  by  you,  I  shall  report  as 
concisely  as  possible  the  information  gained  and 
the  results  obtained  by  numerous  experiments 
carried  on  and  observed  for  two  seasons.  I 
shall  here  use  in  this  paper  as  a  part  of  it,  a  re- 
port presented  to  the  Santa  Clara  County  Hor- 
ticultural Society,  August  6,  1881,  by  Mr.  D. 
C.  Vestal  and  myself,  with  such  revision  and 
correction  as  another  year  has  shown  to  be 
needed,  and  with  added  memoranda  to  the  ex- 
periments detailed,  in  order  to  present  their 
full  effects  after  a  lapse  of  more  than  a  year.  I 
shall  also  detail  other  experiments,and  shall  re- 
fer to  work  done  on  an  extensive  scale  for  the 
destruction  of  the  scale  pests,  and  which  has 
shown  most  gratifying  result.-. 

All  scale  insects  impair,  to  a  greater  or  less 
degree,  the  vitality  and  productiveness  of  the 
tree  or  plant  upon  which  they  live.  Of  the 
seven  species  which  have  here  been  observed  as 
infecting  our  deciduous  orchard  trees  and  fruits, 
five  are  of  frequency  and  of  such  importance  as 
to  attract  the  attention  of  orchardists.  These 
are  the  Lecanium  Olecz,  Aspidiotus  Rapax, 
Aspidiotus  Conchiformis,  Aspidiotus  Pernic- 
iousus  and  the  Icerya  Purchasi,  the  two  last 
named  being  the  most  dangerous  of  all  scale 
pests  which  the  orchardist  has  to  encounter. 

Lecanium  Oltte. — This  scale  is  beginning  to 
attack  other  trees  than  the  orange  and  its  kin- 
dred. A  year  since  I  examined  an  orchard 
where  it  existed  in  overwhelming  numbers 
upon  the  German  prune,  Brigg's  Hed  May  and 
the  Early  Crawford  peaches,  upon  the  Moor- 
park  apricot  trees,  and  most  of  all  upon  the 
Petite  prune  d'agen  trees.  This  is  believed  to  be 
the  direct  result  of  planting  a  few  orange  trees 
close  by.  Mr.  Ellwood  Cooper  has  written 
fully  upon  this  scale,  and  to  whose  reports  I 
refer  you. 

Aspidiotus  Rapax. — So  named  by  Prof.  J.  H. 
Com  stock.  This  scale  is  rapidly  spreading,  and 
is  now  found  in  many  places  where  unknown 
a  year  or  two  ago.  It  seems  to  be  most 


337 


nent  in  Santa  Cruz  county,  where  it  can  be 
abundantly  found.  I  have,  during  the  past  two 
seasons,  observed  it  in  many  places  in  Santa 
Clara  county,  and  have  had  specimens  sent  me 
from  San  Lorenzo,  Alameda  county,  where  it 
was  abundant  upon  pear  trees,  a  branch  sent 
being  well  covered  with  the  old  scale,  and  also 
newly  hatched  young  crawling  about. 

This  scale  seems  to  be  native  to  the  willow 
and  alder  and  other  indigenous  trees.  It,  how* 
ever,  is  found  in  great  numbers  upon  acacia 
trees,  upon  the  black  locust  and  poplar,  and 
upon  some  of  our  orchard  trees,  as  the  pear  and 
apple.  This  scale  somewhat  resembles  the 
Aspidiotus  perniciosus,  and  by  many  is  con- 
founded with  it,  but  it  is  not  to  be  compared  to 
the  latter  for  destructiveness. 

Aspidiotus  Conchiformis.— The  one  longest 
known,  and  which  was  discovered  and  described 
in  Maine  in  1794,  has  ever  since  that  time  in- 
fested the  apple  tree  particularly,  although 
found  upon  other  fruit  trees  and  upon  the  cur- 
rant. This  is  now  found  in  great  numbers  upon 
almost  all  old  apple  trees  on  this  coast,  and  is 
commonly  known  as  the  bark  louse  or  the 
oyster- shell  scale.  It  may  be  found  described 
in  works  on  entomology.  This  species  has  not 
caused  so  much  injury  as  to  alarm  fruit  grow- 
ers to  any  great  extent,  although  it  is  described 
by  Dr.  Packard  as  doing  more  injury  to  the 
apple  tree  than  any  other  insect  known. 

Cottony  Cushion  Scale. 

Next  will  be  described  a  comparatively  new 
scale  heretofore,  but  one  which  has  within  the 
last  two  or  three  years  been  ravaging  many  lo- 
calities in  widely  different  parts  of  the  State. 
This  is  the  so-called  dorthesia,  or,  as  named  by 
Maskell,  Icerya  Purclmsi,  and  called  by  Mr. 
Matthew  Cooke  the  cottony  cushion  scale. 

This  scale  has  been,  it  is  asserted,  known  to 
be  on  the  acacia  for  seven  years  in  San  Jose,  but 
it  is  only  during  the  past  and  present  seasons 
that  it  has  attracted  attention.  Its  great  pro- 
litiouess  and  its  destructive  abilities  have  called 
widespread  attention  to  it.  This  pest  attacks 
everything  in  the  way  of  tree,  vine  or  shrub; 
all  the  evergreens  as  well  as  deciduous  trees 
llhatifatt  in  its  way  are  attacked,  and  every  orna- 


mental  shrub  on  the  lawns  of  souie  portion  of 
our  cities  will  show  its*  presence.  The  ivy,  even, 
is  not.  prQof  .against  ?,t.  In  San  K»fael,  San 
Mateo\  Sruifcu  Errbaru  aad  Los  Angelas  it  is  well 
established.  While  in  San  Jose  it  has  not  this 
season  caused  so  great  damage  as  last,  yet  in  the 
citrus-growing  regions  it  is  becoming  one  of  the 
most  serious  pests  they  have  to  encounter,  and 
it  is  even  stated  that,  should  its  ravages  not  be 


Larvse 


On  the  Twig. 


Cottony    Cushion    Scale— Icerya   Purchasi 

checked,  orange  and  lemon  culture  will  have  to 
be  abandoned. 

From  the  rapid  destruction  which  follows  the 
presence  of  this  scale,  it  is  well  that  it  should 
be  widely  recognized,  and  its  first  invasion  no- 
ticed and  checked.  In  San  Jose,  in  1881,  it  was 
first  noticed  in  May  as  the  fully  developed  fe- 
male, from  which  the  first  brood  of  young  then 
appeared. 


Scale    on  Fruit   and    Twig. 


haps  the  twenty-fifth  of  an  inch  in  length.  The 
body  is  pale  red;  the  six  legs  and  two  antennae 
are  black.  The  antenna-  are  long  and  club- 
shaped,  and  have  from  six  to  nine  joints,  as 
they  are  further  matured.  The  antennas  are 
covered  with  long  hairs,  which  bristle  forth 
prominently.  The  eyes  are  small  and  black. 
Between  the  pair  of  forelegs  on  the  under  side 
of  the  body  is  to  be  seen  the  beak  or  sucker,  by 
which  the  insect  secures  its  nourishment. 

The  females  partly  grown  are  of  a  variety  of 
colors,  orange  red  mostly,  and  spotted  over 
with  white  and  green;  some  are  nearly  entirely 
a  dirty  white,  and  many  are  a  pea  green.  It 
seems  that  the  coloring  matter  of  the  plant  they 
are  upon  colors  them  to  some  extent.  Their 
body  is  ovoid  and  elongated  and  flattened,  the 
back  being  ridged  up  with  several  segments 
quite  prominent.  Around  the  rim  of  the  body 
are  a  multitude  of  hairs,  standing  out  promin- 
ently. Around  the  rear  half  of  the  body  on  its 
rim  are  a  row  of  tubercles  or  spinarets,  from 
which  a  white  secretion  issues,  forming  a  cot- 
tony cord,  and  these  placed  side  by  side  and  the 
interspace  filled  up  by  the  same  material  run- 
ning lengthwise  the  body  and  projecting  from 
it,  gives  the  whole  a  ribbed,  satin-like  appear- 
ance whitish  in  color.  Gradually  as  the  insect 
matures  these  projecting  ridges  approach  each 
other  at  the  ends,  and  are  joined  together  and 
curved  under  slightly  at  the  point,  while  the 
sides  are  at  the  same  time  curved  under  the 
whole  length,  and  the  edges  joined  together  like 
a  flat  ribbon- like  band,  the  whole  forming,  when 
complete,  a  soft  elastic  white  sack,  the  size, 
and  somewhat  the  shape  of  a  medium  sized 
white  bean.  The  length,  when  mature,  is  about 
three-eighths  of  an  inch;  the  width  one-fifth  of 
an  inch. 

Inside  the  sack  are  deposited  the  eggs  of  the 
female,  among  the  interstices  of  a  ma^s  of  cot- 


Ferrmla. 


Male 


Larva- 


SAN    JOSE    SCALE    INSECT-Aspidiotus  Perniciosus. 


This  present  season  of  1882  the  first  young 
appeared  May  25th,  the  mother  insect  having 
gradually  matured  her  eggs  from  the  opening  of 
spring  until  the  young  were  hatched.  The  egg 
of  the  Icerya  is  small,  pale  or  orange  red, 
elongated  and  ovoid.  The  young  just  hatched 
out  are  very  active,  and  are  very  minute,  per- 


ton-like  fiber,  which  under  a  high  magnifying 
power  is  shown  to  be  round,  and  not  more  than 
one-sixth  part  the  thickness  of  pure  cotton 
fiber,  with  which  it  was  compared  in  the  same 
field.  This  mass  of  cottony  fiber  is  filled  with 
a  great  amount  of  granular  matter,  for  the 
purpose,  it  may  be,  of  affording  sustenance  to 


the  young  insects  within  the  sack.  The  young 
hatch  out  in  this  sack,  and  make  their  way  out 
into  the  world  through  a  rent  in  the  soft  and 
tender  underside  of  the  sack. 

The  female,  after  finding  her  home  and  dur- 
ing maturity,  does  not  move,  although  she  does 
not  lose  her  legs,  but  clings  tenaciously  with 
her  feet  to  her  support,  leaving  the  body  tipped 
up  in  the  rear  and  the  cottony  mass  movable  in 
any  direction.  The  male  insect  was  only  found 
during  a  period  of  about  two  weeks  from  Sept. 


On  the  Twigf. 


grown  and  with  the  young  hatched  out  and 
crawling  in  the  same  sack.  In  1881  they  rap- 
idly increased  from  about  the  first  of  August, 
and  were  continually  appearing,  and  still  hatch- 
ing out  in  December. 

Every  female,  it  is  estimated,  produces  from 
200  to  500  young.  The  young  will  mature  and 
produce  a  new  brood  in  about  three  months. 
Where  this  scale  infests  deciduous  trees  it 
may  be  readily  destroyed  by  the  application 
now  found  to  be  successful  in  treating  the  Aspi- 


Larvee. 


BLACK    SCALE  -Lecanium  Oleee. 


25tb.  This  was  the  observation  of  1881,  when 
I  found  them  in  great  numbers.  I  have  failed 
to  find  the  male  insect  this  season.  It  has  a 
long  red  body,  six  legs  and  one  pair  of  very  long, 
dark  and  transparent  wings,  prominent  eyes  and 
antenme  very  long  and  covered  with  hairs,  ar- 
ranged very  much  as  the  feathers  of  a  peacock. 
The  antennae  are  16  or  17  jointed.  The 
winged  male  is  easily  seen  and  easily  caught,  as 
it  moves  slowly  about,  and  is  not  readily  dis- 
turbed so  as  to  fly  away.  The  female  insect 
lives  upon  the  trunk  of  the  tree  and  large 


diotus  Perniciosus,  and  detailed  further   on  in 
this  report. 

Where,  however,  evergreens  are  involved  it 
is  a  far  more  serious  problem.     The  best  treat- 
ment for  the  Icerya,  so  far  found,  is  that  used 
I  by  Mr.  Cooper,  of  a  strong  and  hot  infusion  of 
j  tobacco,  applied  by  spray  as  near  as  may  be  at 
!  130°. 

Aspidiotus  Perniciosus. 

By  far  the  most  injurious  scale  pest  infesting 
j  our  orchard  trees  and  fruit  is  the  new  species  of 
!  Aspidiotus,  which,  so  far  as  known,  originated 


TBCE    OYSTER    SHELL    BARK    LOUSE— Aspidiotus  Conchiformis. 


limbs  and  down  to  the  smallest  twigs, 
around  which  it  may  be  seen  clinging  in  clus- 
ters sufficiently  great  to  completely  hide  the 
branch;  aleo  upon  the  leaf,  along  the  stem  and 
ribs  of  which  it  is  fixed,  both  above  and  below, 
although  more  abundant  on  the  underside  of  the 
leaf. 

There  are  three  broods  of  this  insect  in  the 
season ;  the  first  appearing  in  May,  the  second 
in  August  and  the  third  in  October,  or  about 
three  months  apart.  I  have  just  observed,  Oc- 
tober 15tb,  the  mature  female  with  eggs  fully 


in  San  Jose,  and  for  some  years  was  confined  to 
this  locality.  It  has  been  known  as  the  San 
Jose  small,  round,  black  scale  and  named  by 
Prof,  foinstock  Aspidiotus  perniciosus.  The 
spread  of  this  scale  over  the  State  has  been 
gradually  taking  place,  until  now  it  can  be 
found  in  a  number  of  the  fruit-growing  counties, 
notably  San  Joaquin,  El  Dorado,  Nevada, 
Placer,  Sacramento,  Yolo,  Solano,  Sonoma,  Ala- 
meda,  Santa  Cruz,  San  Benito  and  others,  and 
I  am  told  even  in  Humboldt  in  the  north  and  in 
the  southern  counties.  This  scale  produces  ter- 


rible  results  in  an  orchard  when  once  estab- 
lished. Its  ravages  have  caused  widespread 
alarm,  and  unless  checked  soon  causes  entire 
destruction  of  the  trees  infested.  The  trees  be- 
come entirely  covered  with  the  scale,  so  that  no 
portion  of  the  bark  can  be  seen.  The  fruit  also 
becomes  covered  in  the  same  manner  and  is  ren- 
dered unfit  for  use.  The  losses  caused  by  the 
ravages  of  this  insect  cannot  be  easily  computed. 
Whole  orchards  are  literally  destroyed  by  it. 
In  many  cases  those  who  have  recognized  its 
presence  and  destructive  power  in  time  have 
made  most  strenuous  efforts  to  stay  its  spread 
and  save  their  trees,  but  it  has  hitherto  been,  to 
a  great  degree,  discouraging,  owing  to  the  diffi 
culties  encountered  in  fighting  an  unknown  foe. 
Within  the  past  two  years,  however,  great 
progress  has  been  made  in  destroying  this  in- 
flect, and  it  is  now  considered  certain  that  we 
have  an  efficient  means  of  ridding  ourselves  of 
one  of  the  most  dangerous  pests  known  to  fruit 
growers. 

The  trees  attacked  embrace  every  kind  of 
deciduous  fruit  trees  except  the  Black  Tarta- 
rian cherry,  and  it  is  supposed  two  or  three 
other  black  cherries.  Some  varieties  are  less 
liable  than  others  to  its  attacks,  but  we  have 
found  it  upon  all  other  trees  than  those  ex- 
cepted  above. 

Poplar  and  other  ornamental  and  shade  trees 
give  it  a  support.  It  infests  hedges  of  Osage 
orange  and  the  wild  cherry,  many  of  which 
have  been  destroyed  in  the  past  two  years,  and 
have  been  dug  out.  It  is  found  on  the  currant, 
and  quickly  destroys  the  bush.  It  has  been 
found  upon  rhubard,  and  tomato  plants  growing 
in  orchards  among  infested  trees.  This  scale 
evidently  prefers  some  varieties  of  trees,  but 
yet,  when  placed  upon  others  not  so  well  liked, 
will  stay  and  colonize  to  some  extent. 

The  effect  of  this  scale  insect  upon  the 
tree  is  peculiar.  After  a  short  residence 
there,  the  green  layer  of  the  bark  be- 
comes stained  a  very  dark  red  color,  which 
continues  until  the  death  of  the  limb  or 
f  ree  unless  the  insect  be  killed.  The  bark  may 
then  be  restored  to  its  normal  color  and  health. 

A  Financial  Aspect. 

The  damage  in  Santa  Clara  county  has  already 
become  so  great  as  to  cause  the  most  serious 
losses  not  alone  to  the  fruit  growers,  but  also  to 
the  public  at  large — and  from  the  orchards  ef- 
fected has  greatly  lessened  the  revenue  which 
lias  been  derived  from  the  production 
and  sale  of  fruit.  One  instance  stated  defi- 
nitely will  suffice  to  show  these  losses. 

This  orchardist  states  (1881)  that  he  has  2,000 
trees  badly  infested  with  scale;.  1,000  of  these 
trees  are  totally  destroyed,  and  will  be  dug  out 
ibis  season;  the  balance  are  badly  injured,  but 
can  probably  be  saved.  This  portion  of  his  or- 
chard in  health  returned  at  least  $5,000  per 
year.  His  loss  on  crop  from  these  trees  in  1880 
\vas  over  $2,000.  For  1881  there  was  a  total 
loss  of  crop  on  1,500  trees.  This  orchard  has 
regularly  paid  an  interest  of  10%  on  $1,000  per 
"ere.  The  scale  pest  alone  has  cost  a  loss  of 
820,000  to  the  owners. 

Further  on  reference  will  again  l>e  made  to 
this  orchard.  The  Assessor's  roll  for  1881  re- 
ports in  this  county  335,537  bearing  trees  of  the 
apple,  pear,  plum  and  peach.  This  does  not 


include  the  large  number  of  trees  which  have 
been  destroyed  and  are  unfruitful;  neither  the 
immense  number  of  young  trees  that  have  been 
planted,  but  not  yet  paying;  and,  as  observed, 
it  leaves  out  the  large  number  of  other  varie- 
ties, cherries,  a] moms,  apricots,  etc.,  in  bearing, 
which,  it  is  estimated,  would  make  a  grand 
total  of  1,000,000  trees.  Should  the  losses  ex- 
perienced by  the  orchardists  now  suffering  be 
carried  out  to  all,  you  can  readily  estimate  the 
astounding  result.  The  value  of  the  Santa 
Clara  county  fruit  crop  for  1880  was  returned 
at  $976,475,  notwithstanding  the  immense 
losses  incurred.  The  sworn  statement  of  the 
Assessor,  now  before  rne,  says  "That  all  fruit 
trees  in  Santa  Clara  county  are  assessed  as  im- 
provements at  the  following  prices:  Trees  in 
full  bearing,  free  from  scale,  $1.50  per  tree; 
trees  bearing,  affected  with  scale,  from  .00  to 
50  cts.  per  tree,  and  that  there  is  a  large  num- 
ber of  orchards  situated  east  and  northeast  from 
the  city  of  San  Jose,  badly  infested  with  scale 
(and  after  naming  some,  say?),  and  in  conse- 
quence are  assessed  at  .00  to  50  cts.  per  tree." 
From  this  it  will  be  seen  that  the  revenue  de- 
rived from  taxation  is  seriously  affected  by  the 
presence  of  this  pest  upon  our  orchard  trees. 

The  Assessor's  roll  for  1882  gi^es  of  the  four 
varieties  of  trees  named  above — apples,  peaches, 
pears  and  plums — bearing  trees  subject  to  tax- 
ation 280,347,  a  deduction  from  the  previous 
year's  assessment  of  55,190  trees.  This  loss  is  in 
fact  upon  apple,  plum  and  peach  trees,  as  the 
young  pear  trees  coming  into  bearing,  and  be- 
ing assessed  for  the  first  time,  more  than  equal 
the  loss  on  that  variety.  So  it  is  seen  that  the 
loss  in  assessed  value  on  these  three  kinds  of 
trees  totally  destroyed  has  amounted  in  the  one 
year  to  $82,785.  This  is  actually  but  a  small 
part  of  the  loss,  as  other  varieties  of  trees  des- 
troyed, and  the  losses  of  previous  years  from 
the  scale  as  well  as  the  reduced  value  of  trees 
affected  but  still  bearing,  cannot  well  be  enu- 
merated. These  trees  were  destroyed  before 
the  application  of  proper  remedies;  now,  how- 
ever, from  the  knowledge  of  correct  treatment, 
these  losses  will  soon  cease,  and  the  taxable 
property  of  the  county  be  immensely  in- 
creased. I  feel  assured  that  the  next  assess- 
ment will  show  a  decided  improvement.  Thus 
the  magnitude  of  this  evil  becomes  apparent, 
and  the  problem  to  be  solved  is  of  vast  impor- 
tance. 

Description  of  this  Pest. 
From  the  study  we  have  given  to  this  scale 
during  the  past  three   years  it  may   be   briefly 
described  as  follows:  The  scale  insect  is  massed 
upon  the  bark  of  the  tree  and  fruit  as  well,  the 
scale  of  a  dark  gray  or  blackish  and  tough   ma- 
terial which  covers   the  insect  being  very  small 
and  round  in  shape  over  the  female,  while  that 
covering  the  male  is  much  smaller  and  elongated 
on  one  side.     In  both,  the   higher  and   central 
portion  of  the  scale   has  a  yellowish  color,  and 
directly  under  which  may  be  found  the  insect 
itself,    which  is  soft   and   delicate  in  structure 
and  of  a  pale  straw  color.      There  is  no  con- 
nection between  the  cover  and  the  insect,  which 
is  merely  protected  by  it  from  harm.  The  shell- 
I  like  scale  is  formed  by  either  the  cast-off  skins 
i  of  the  larva  or  by  a  waxy  secretion  of  the  body 
j  of  the  insect.  The  microscope  shows  the  young 
i  female  insect  oval  in  shape  and  flattened.    At 


first  it  is  very  small  and  hardly  perceptible  to 
the  naked  eye,  but  careful  observation  will  de- 
tect it  as  a  minute  yellow  dot  on  the  bark  of 
the  tree,  crawling  about  with  the  six  legs  with 
which  it  is  provided,  and  seeking  a  favorable 
locality  upon  which  to  fix  itself  for  life.  It 
will  crawl  about  for  only  a  day  or  two,  and  then 
fastens  itself  to  the  bark  by  a  beak-like  pro- 
tuberance which  it  inserts,  and  procures  nour- 
ishment from  juices  of  the  tree.  Immediately 
upon  fixing  itself  it  begins  to  be  covered  with 
a  silvery  material,  which,  as  it  grows  older,  is 
gradually  changed  in  color  to  a  very  dark  hue, 
and  enlarges  to  the  size  of  about  one-sixteenth 
of  an  inch  in  dia.neter.  The  insect  soon  after 
fixing  itself  loses  its  legs  and  antennce,  and  thus 
remains  through  life,  keeping  its  flattened  shape 
but  growing  wrinkled  and  almost  round,  gradu- 
ally increasing  in  size  to  perhaps  one-sixteenth 
of  an  inch  in  width  and  one-fifteenth  of  an  inch 
in  length  when  full  of  young.  After  the  young 
emerge  it  is  dried  up  and  disappears.  We  have 
counted  from  the  female,  when  full  of  young,  be- 
tween 50  and  60  of  the  minute  sacks  which  con- 
tain  the  young  perfectly  formed  insects  ready 
to  crawl  about.  The  young  male  insect  is  pro- 
duced in  the  same  manner  and  at  the  same  time, 
though  not  in  such  numbers;  perhaps  half  a 
dozen  males  to  a  hundred  females.  In  size  the 
male  is  about  one -third  that  of  the  female,  and 
in  shape  very  different,  being  elongated  and 
more  angular,  provided  with  six  legs  placed 
differently  up  on  the  body,  with  two  antennae 
and  two  eyes,  and  with  a  teat-like  protuberance 
at  the  rear  end  of  the  body  ending  with  a  point. 

At  this  stage  of  its  existence  the  male  has  no 
wings,  and  it  cannot  be  discerned  without  the 
aid  of  a  magnifying  glass.  The  color  of  the 
young  male  is  not  a  yellow,  but  of  a  steej-like 
or  whitish  hue  It  crawls  about  and  fixes  it- 
self upon  the  bark,  as  does  the  young  female, 
and  becomes  covered  with  a  scale  in  the  same 
manner,  but  which  is  elongated  upon  one 
side,  and  not  more  than  one-half  the 
size  of  the  scale  of  the  female.  The  male, 
after  remaining  its  allotted  tim'e  in  the  pupa 
state,  emerges  as  a  fully  developed  insect, 
having  eyes,  antenne,  six  legs  and  one  pair  of 
very  long  wings  of  a  reddish  and  transparent 
appearance,  and  the  protuberance  at  the  rear 
end  of  the  body  is  developed  into  a  very  long 
tapering  point,  nearly  as  long  as  the  body  it- 
self. The  perfect  winged  male  is  so  minute  it 
can  with  great  difficulty  be  discerned  by  the 
naked  eye,  crawling  and  flying  about  in  search 
of  the  female,  which  it  impregnates  under  the 
scale  and  then,  having  fulfilled  its  mission,  it 
dies. 

In  the  season  of  1880  we  saw  the  winged 
males  first  appear  on  March  23  i,  and  in  great 
numbers  for  a  few  days.  The  first  brood  of 
young  scales  appeared  the  latter  part  of  April. 
Oa  June  27th  we  found  the  males  from  the  first 
brood  under  the  scales  and  nearly  developed 
with  appendages  and  wing  pads,  and  on  July 
2d  large  numbers  of  them  flying  about;  also  as 
late  as  July  25fch,  and  still  later,  on  August 
2d,  a  few  were  seen.  On  July  23d  the  trees 
were  covered  with  the  young  of  the  second 
brood;  August  2d  the  young  males  of  the 
second  brood  were  found  crawling  about. 
Bark  scraped  clean  on  the  23d  of  July  was 
found  on  the  25th  alive  with  young  insects,  and 


some  of  them  already  commencing  to  be 
covered  with  scale.  As  it  was  expected  at  the 
time  these  observations  were  made,  a  third 
brood  would  appear  about  October,  so  we  found 
it.  On  October  17th  we  found  the  male  scale 
insect  in  the  first  pupa  stage  of  development  in 
the  winged  form,  and  also  on  the  same  day 
found  the  perfect  winged  insect  of  the  third 
brood  moving  about  on  the  tree. 

These  facts  prove  conclusively  that  there  are 
three  distinct  broods  of  these  insects  in  the  sea- 
son, the  earliest  portion  of  the  first  brood  about 
March  23d,  of  the  second  brood  about  July  2d, 
and  of  the  third  brood  about  October  17th,  there 
being  apparently  an  interval  of  14  to  15  weeks 
between  the  different  broods  of  the  season.  The 
young  female  insects  were  found  crawling  about 
through  the  season  and  as  late  as  the  last  of 
November.  The  last  brood  remains  through  the 
winter  under  the  scale  until  the  approach  of 
warm  weather  in  the  spring,  when  they  again  ap- 
pear. 

While  the  Aspidiotus  Conchiformis  will  de- 
velop but  one  or  at  most  two  broods  per  season, 
this  new  species  of  Aspidiotus  will  produce  three 
broods,  and  each  female  probably  50  young. 
This  present  season  of  1882  has  been  in  the  de- 
velopment of  fruit  and  insects  about  three  weeks 
or  more  later,  consequently  the  appearance  of 
the  scale  was  not  expected  as  early  as  last  year. 
The  first  winged  male  scale  insects  of  this 
species  were  discovered  this  year  on  April  25fch 
crawling  about  on  an  English  hawthorn  tree. 
At  that  time  no  young  female  scale  insects  were 
to  be  found,  but  the  old  females  under  the  scales 
were  approaching  maturity,  and  in  due  time  the 
young  appeared. 

Foes  of  Scale  Insects. 

The  natural  enemies  of  the  scale  insect  are 
the  larvae  of  some  varieties  of  the  Coccinellidce, 
or  lady-birds. 

The  season  of  1881  developed  in  great  num- 
bers an  important  enemy  of  the  scale,  viz. :  the 
Chrysopa  or  lace-winged  fly,  the  larvae  of  which 
prey  upon  it.  This  is  a  beautiful,  slender  and 
delicate  fly,  bright  green  in  color,  with  large 
golden  eyes,  and  very  long  wings  like  lace. 
The  eggs  are  very  minute,  white  and  oval  in 
shape,  and  are  attached  by  a  long  and  slender 
pedicle  to  the  underside  of  leaves  or  the  fruit. 
The  larva  is  about  one- quarter  of  an  inch  long, 
slender,  and  tapering  from  the  middle  toward 
both  ends.  It  is  provided  with  jaws,  each  per- 
forated, through  which  it  sucks  the  juice  of  its 
victim. 

Remedies  for  Scale  Insects. 

In  1881  Mr.  J.  H.  M.  Townsend,  of  the  Santa 
Clara  County  Horticultural  Society,  kindly 
placed  at  our  disposal  a  large  number  of  trees 
infested  with  scale  for  the  use  of  the  committee 
in  making  such  experiments  as  were  desired. 
A  series  of  careful  experiments  for  the  destruc- 
tion of  the  scale  pest  were  made  and  the  results 
carefully  noted.  "Other  experiments  had  been 
under  way  in  our  own  orchards  for  many 
months. 

These  exprimenta  demonstrated  on  one  hand 
the  inefficiency  of  many  applications,  and  on 
the  other  hand  showed  a  certain  means  for  the 
destruction  of  the  scale  insect.  The  remedies 
which  have  proven  successful  will  destroy  all 
the  varieties  of  scale,  as  the  one  under  treat- 


ment  is  the  most  difficult  of  all  to  overcome. 
A  portion  of  these  experiments  are  numbered, 
and  the  results  obtained,  stated  as  observed,  at 
different  dates  up  to  this  time,  October,  1882, 

No.  1.  Concentrated  lye  of  the  American  Lye 
Co.,  one  pound;  water,  two  gallons.  Feb- 
ruary 22,  1881 — Applied  by  spray  upon 
two  peach  trees  infected  by  scale;  washed  in 
the  afternoon  when  the  trees  were  dry;  effect, 
scale  killed ;  the  tenderest  wood  was  killed  also. 
July  5,  1881 — New  wood  grown  over  the  trees 
four  and  five  feet  long. 

No.  2.  Concentrated  lye,  one  pound;  water, 
two  gallons.  March  10,  1881— Applied  by  spray 
upon  two  peach  trees  infested  by  scale,  washed 
in  the  morning  when  the  trees  were  damp  with 
dew.  July  5,  1881— Scale  killed;  buds  and 
twigs  not  injured;  fruit  abundant  and  trees 
most  healthy. 

No.  3.  Concentrated  lye,  one  and  one-half 
pounds;  water,  one  gallon.  June  23,  1881 — Ap- 
plied by  pouring  from  a  dipper  upon  two  pear 
trees  infested  with  scale  and  with  numerous 
limbs  dead.  Lye  so  strong  as  to  burn  bark  and 
foliage.  August  2,  1881 — Scale  entirely  des- 
stroyed;  bark  being  restored  and  new  foliage 
appearing. 

No.  4.  Concentrated  lye,  one  pound;  water, 
one  gallon.  July  5,  1881 — Applied  by  spray 
upon  a  large  apple  tree  badly  infested  by  scale; 
bark  and  leaves  burned.  August  2,  1881 — Scale 
killed;  green  layer  of  bark  being  rapidly  re- 
stored and  new  leaves  and  blossoms  appearing 
all  over  the  tree.  The  foregoing  trees  have 
since  been  mostly  killed  by  the  application  of  a 
low  grade  of  coal  oil. 

No.  5.  Concentrated  lye,  one  pound;  water, 
one  gallon.  February,  1881 — One  almond  tree, 
one  Easter  Beurre  pear  tree  and  two  apple  trees, 
grafted,  were  washed  by  brush  with  this 
strength  of  lye  in  order  to  destroy  the  red 
spider  and  its  eggs,  which  could  not  be  de- 
stroyed by  previous  applications  of  lye,  one 
pound  to  five  gallons,  and  also  one  pound  to 
three  gallons;  another  and  the  main  reason 
being  to  ascertain  the  effects  of  very  strong  lye 
upon  the  trees.  No  scale  upon  these  trees. 
This  application  destroyed  the  red  spider  and 
its  eggs  on  these  trees  so  that  it  did  not  appear 
for  months;  but,  however,  later  on  the  trees  be- 
came again  infested.  While  the  strong  lye  will 
destroy  a  large  number  of  the  eggs  of  the  red 
spider  it  is  found  that  all  cannot  be  reached. 
The  effect  upon  the  bark  and  health  of  these 
trees  was  wonderfully  good,  the  bark  being  very 
smooth  and  having  a  bright  green,  velvety  ap- 
pearance and  totally  free  from  all  moss  or  other 
parasites. 

No.  6.  Concentrated  lye,  one  pound;  water, 
one  gallon.  The  experiments  in  this  number 
were  made  upon  a  section  of  orchard  in  a  square 
block  comprising  357  Ickworth  plum  trees,  cut 
down  and  grafted  into  Petite  prune;  some  year- 
ling prune  trees  having  been  put  in  in  places 
and  washed  as  were  the  plums,  of  these  126 
trees  were  washed  in  February,  1881,  with  the 
above  strong  lye,  applied  with  a  brush.  Among 
the  357  trees  were  eight  trees  badly  infested 
with  scale.  No  others  had  any  scales  upon 
them.  The  infested  trees  were  scattered  about 
as  follows,  and  washed  as  indicated: 


No.  10  in  first  row  and  4  in  llth  row  were 
washed  with  lye,  one  pound  to  three  gallons  of 
water.  The  effect  was  not  quite  sufficient  to 
completely  destroy  the  scale,  though  so  in- 
jured that  they  did  not  breed.  Afterward 
these  two  trees  were  washed  with  one  pound  to 
one  gallon,  and  this  effectually  ended  the  scale. 
No.  7  in  Cfch  row,  10  in  7th  row,  11  in  12fch 
row,  8  in  14th  row,  3  in  17th  row  and  11  in 
17ch  row  were  washed  with  lye,  one  pound  to 
one  gallon  of  water,  with  the  effect  of  com- 
pletely destroying  every  scale  upon  them,  and 
not  one  has  appeared  upon  any  of  these  trees* 
since  that  time.  These  trees  have  been  in  the 
finest  possible  condition  from,  the  time  of  this 
application. 

Among  the  trees  not  washed  with  the  strong 
lye,  two  were  found,  in  June,  1882,  to  have 
scale  upon  them;  one  of  these,  the  top  having 
become  badly  broken  by  wind,  was  dug  out  and 
burned,  the  other  was  washed  soon  as  discov- 
ered with  the  whale-oil  soap  and  sulphur  mixt- 
ure; owing  to  the  foliage  upon  the  tree  not 
every  part  of  it  could  be  touched.  Yet,  how- 
ever, the  scale  was  destroyed,  so  far  as  could  be 
found. 

No.  7.  Concentrated  lye,  1  pound  to  one  and 
one-half  gallons  water.  Five  Bartlett  pear  trees 
obtained  from  the  nursery  and  planted  in  1881 
and  scattered  among  a  considerable  number,  al- 
though carefully  examined  at  the  time  for  scale,, 
were  found  in  June,  1881,  to  have  a  few  scales 
upon  them.  These  were  at  once  washed  with 
the  above  strength  of  lye,  which  destroyed  the 
scale  completely  upon  three  of  thoseotrees,so  that 
none  subsequently  appeared.  On  two  of  them, 
however,  a  live  scale  or  two  must  have  remained 
on  the  trunk  of  the  tree  at  the  surface  of  the 
ground  untouched  by  the  lye,  as  in  September 
following  a  few  young  scales  were  discovered, 
located  close  to  the  ground.  These  were  again 
washed  in  the  same  manner.  Since  that  wash- 
ing no  scale  has  been  found  upon  either  of  these 
trees  until  this  month  (Oct.  16,  1882).  On  one 
of  them  has  been  found  a  few  young  scale.  The 
tree  was  immediately  washed  with  the  whale- 
oil  soap  and  sulphur  mixture.  On  another 
Bartlett  pear  tree,  not,  however,  numbered  with 
the  above,  was  found  some  scales,  Nov.  7,  1881. 
This  tree,  being  entirely  dormant,  was  washed 
with  lye  one  pound  to  one  gallon  water,  com- 
pletely destroying  the  scale,  as  none  can  be 
found  on  it  this  year.  Among  the  Yellow  Egg 
plum  trees,  one  was  found  January,  1882,  with 
scale  upon  it,  and  washed  at  once  with  lye  one 
pound  to  one  gallon  water,  and  repeated  in  Feb- 
ruary. No  scale  were  left,  as  none  can  ba  found 
at  this  date.  Another  Egg  plum  tree  was  found 
infested  in  June  of  this  year.  To  this  was  ap- 
plied, by  a  brush,  the  whale-oil  soap  and 
sulphur  mixture  with  some  lye  added. 
No  scale  can  now  be  found  upon  it. 

The  trees  in  experiments  five, six  and  seven  are 
in  an  orchard  of  50  acres.  I  have  constantly 
and  carefully  watched  all  these  trees,  and  at 
this  date  no  scale  can  be  discovered  in  the  en- 
tire orchard.  Should  any  hereafter  appear,  the 
treatment  will  be  by  lye  one  Ib.  to  one  gallon 
water.  With  this  success  in  my  two  years'  in- 
dividual practice,  I  feel  justified  in  repeating 
the  statement  I  made  at  the  first  State 
Fruit  Growers'  Convention,  that  young  orchards 


can  be  kept  free  from  the  Aspidiotus  perniciosus 
by  the  right  use  of  concentrated  lye  as  a  winter 
wash,  and  the  whale  oil  soap  and  sulphur  mix- 
ture for  summer. 

In  the  following  experiments  the  trees   were 
all  badly  infested  with  scale: 

8.  Concentrated  lye,  one  and  one-half  IBs;  wa- 
ter one  gallon.     June  24,  1881 — Applied  to  two 
Clairgeau  pear  trees;  brush   used   in   order   to 
save  foliage;  many  limbs  dead    from   effects   of 
scale.       Jane  27— Trees  burned    considerably; 
scale  killed  where  reached.     July  2d — Much  of 
the  bark  showing  a  healthier  appearance.    July 
23d— Trees  still  better.     August  2d — No  sign  of 
scale;  green  layer  of  bark  being   restored  very 
rapidly;  the  fruit  quite  clean,  because  no  scales 
of  second  brood  were  upon  it.    April  25,  1882 — 
Examined  the  trees,  and  found  a  very   healthy 
top.  and  with  new  bark  where  burned  with  the 
lye  when  washed  in  the  summer.     All  the  sur- 
face was  not  touched  by  the  lye,  and  where  not 
washed  the  scales  still  existed.     Wherever  the 
bark  was  washed,  owing  to  the  time  that  it  was 
done,  it  was  cracked  across.      Yet  underneath 
this  cracked  surface  was  found  new  and  healthy 
bark.     October   14,    1882— There   has     been  a 
good  growth  of  new  wood  this   season,  and  the 
under  bark  has  maintained  its  fresh  and  healthy 
appearance  over  entire  tree. 

9.  Concentrated  lye,  one  and  a  half  K»3. ;  wa- 
ter, one  gallon.      June  24,  1881 — Applied  on  a 
portion  of  tree  to  ascertain  the  effect  upon  the 
stain   of  bark.     July   23i— The    bark     where 
washed  shows  much  less  stain;  lighter  in  color, 
and   the  green  layer  being  restored.     August 
2d — Stain  rapidly  disappearing. 

10.  Concentrated  lye,  one  fib. ;  water,  one  gal- 
lon.    July  5,  1881 — Mixed  accurately,  and  ap- 
plied same  day  upon   pear    tree.     July   23d — 
Scale   where  reached  entirely  destroyed;  bark 
burned  by  the   lye,  but  otherwise  healthy  and 
good  where  it  was  previously  sound.     April  25, 
1882,    and    October    14,    1882  —  Observations 
nearly  the   same  as    in  the  preceding  number, 
the  bark  under  the  cracked  outer  layer  being 
all  renewed,  and  with  a  bright,  healthy,  green 
layer  free  from  stain;  free  growth  of  new  wood 
during  the  season. 

11.  Concentrated  lye,  one  pound;  water,  one 
and  one-half  gallons.     Tree  washed  same  time 
as  above  and  with  about  the  same  results,  al- 
though an  unthrifty  tree.      October  14,  1882— 
The  tree  had  been  pretty  well  destroyed  by  the 
scale  last  year,  and  shows  but  a  little  growth 
of  new  wood. 

12.  Concentrated    lye,    one  lb.;   water,    two 
gallons.     Same  as  above,  except   that   the   tree 
was  still  more  thoroughly  ruined  by  scale,  and 
at  this  date  has   not  recovered  ^but  little  new 
wood;  what  there  is,   however,  being  healthy. 

13.  Concentrated   lye,  one  lt>:;  water,    three 
gallons.     This  tree  had  been  washed  by  spray- 
ing April   1,   1881,   with   this  strength  of  lye, 
which   proved  too  weak  to  destroy  the  scale. 
July  23,  1881 — Young  scale  insects  covered  the 
tree;  the  tree  was  left  to  itself  with  that  wash- 
ing.    April  25,   1882— Observed  that  the  scale 
was  abundant  and  fast  accomplishing  the   de- 
struction of  the  tree.     October,  14,  1882 — The 
tree  is   dead   to  within  one  foot  of  the  ground, 
but  from   the  collar  many  new   sprouts  have 
grown. 

No.  14.  Concentrated  lye,  1  lb;  water,  5  gals. 


June  23,  1881 — Applied  to  two  trees,  one 
slightly  and  the  other  badly  infested  with  scale. 
This  wash  was  used  by  pouring  it  upon  the 
trunk  of  the  trees  and  allowing  it  to  run  down 
and  soak  into  the  ground;  the  tops  of  the  trees 
were  not  touched.  This  experiment  was  made, 
as  it  had  been  publicly  stated  that  this  weak 
lye  used  in  this  manner  was  an  effectual  rem- 
edy. July  2,  1881 — No  effect  produced  upon 
the  scale  where  not  reached  by  the  lye. 
August  2,  1881— No  effect  other  than  no- 
ticed above;  scale  only  injured  where  touched 
by  the  lye,  and  second  brood  of  young  scale  in- 
sects  crawling  all  over  the  top  of  the  trees. 
April  25,  1882— Trunk  quite  clean  and 
healthy,  but  the  top  full  of  scale  insects  of  the 
last  season  alive  and  approaching  maturity. 
October  14,  1882— Tree  covered  with  scale, 
old  and  young;  the  trunk,  however,  where 
washed,  appearing  far  more  free  than  the  up- 
per portion;  the  bark  where  washed  is  healthy. 

Use  of  Kerosene. 

In  the  following  experiments  with  kerosene, 
the  action  of  that  agent  was  reported  as  it  then 
appeared  at  the  date  of  report,  but  the  subse- 
quent effects  which  will  now  be  stated,  show 
how  important  it  is  to  allow  ample  time  to 
elapse  before  coming  to  a  conclusion  upon  the 
merits  or  demerits  of  a  particular  proposed 
remedy.  The  use  of  coal  oil  when  the  tree  is 
full  of  sap  is  plainly  shown  to  be  unallowable. 
These  will  be  detailed  as  they  appeared  at  the 
time,  and  also  as  seen  this  season. 

No.  15.  Kerosene,  low  grade  and  heavy,  110 
test.  June  1,  1881 — Applied  to  two  pear  trees, 
spraying,  with  coarse  spray  used  and  oil  thrown 
over  the  entire  trees.  June  27,  1881 — Observed 
that  the  foliage  had  been  killed  and  the  trees 
considerably  affected;  scale  killed.  July  2, 
1881 — New  leaf  buds  coming  out.  July  23, 
1881 — New  foliage  all  over  the  trees,  and  seem- 
ingly new  vigor  throughout;  new  shoots  six 
inches  long;  no  scale  to  be  found,  and  the  green 
layer  of  the  birk  healthy  to  all  appearance. 
August  2d — Foliage  increasing  rapidly  all  over 
the  trees,  and,  apparently,  the  trees  were  gain- 
ing in  health.  Thus  they  appeared  up  to  Au- 
gust, 1881.  The  observation  of  these  trees  on 
April  25,  1882,  showed  a  very  different  state; 
the  trees  were  dead. 

No.  16.  Kerosene,  high  grade,  150  test.  June 

1,  1881 — Applied  by  spray  upon  two  pear  trees. 
June   27,  1881— Observed   that  the  foliage  had 
not  been  killed,  but  that  the  scale  had  all  been 
destroyed;    the    trees     apparently    uninjured. 
July  2d — New  leaf  buds  coming  forth.    August 

2,  1881 — Trees   appear  healthy;   foliage    unin- 
jured; scale   showing  no  signs  of  its  presence, 
and  the  fruit  showing  less  effects  from  scale  on 
account  of  the  wash  it  bad  received.     April  25, 
1882— Trees  were  dead. 

No.  17.  Kerosene,  high  grade  Diamond  brand, 
150  test.  July  27,  1881— Applied  upon  two 
pear  trees  with  a  coarse  heavy  spray  over  entire 
trees;  trees  very  badly  infested.  August  2 — 
Effectually  destroyed  the  scale;  the  trees  and 
foliage  apparently  entirely  healthy.  No  per- 
ceptible effect  upon  the  trees,  but  completely 
dryiug  up  the  scales,  so  that  they  are  blown 
away  by  the  wind.  The  fruit  is  not  affected  by 
the  kerosene,  but  the  scale  upon  it  is  killed, 
and  the  fruit  is  very  clean.  It  is  observed  that 


kerosene  of  150  test  evaporates  rapidly,  and 
leaves  but  little  signs  of  having  been  applied. 
April  25,  1882— One  tree  dead;  the  other  not 
dead  but  nearly  so.  October  14,  1882— Ex- 
animation  showed  trees  to  be  dead. 

No.  18.  Kerosene,  same  brand.  July  27,  1881 
— Applied  upon  a  pear  tree  by  spray  atomizer, 
which  produced  a  very  fine  mist  only.  Aug- 
ust 2,  1881 — The  same  effects  produced  as  in 
No.  17;  scale  appeared  to  be  entirely  destroyed; 
no  apparent  effect  upon  tree  or  foliage.  April 
25,  1S82— Tree  not  dead,  but  with  many  scales 
upon  it.  October  14,  1882 — Old  wood 
dead,  but  new  wood  from  near  the  ground. 

No.  19.  Gasoline.  July  27,  1881— Applied 
upon  pear  tree  by  heavy  syringe  spray  thor- 
oughly over  the  tree  and  foliage.  August  2, 
1881 — Not  effectual  in  destroying  the  scale;  too 
volatile;  many  of  the  insects  killed,  but  a  large 
portion  unaffected;  no  apparent  effect  upon  the 
tree  or  foliage  at  that  time;  on  this  tree  the 
young  male  scales  just  hatched  out  were  found 
crawling  about.  April  25,  1882 — The  tree  has 
been  almost  killed  by  the  scale  infesting  it. 
October  14,  1882— Tree  still  alive,  with  some 
si<»l6  upon  it. 

No.  20.  Gasoline.  July  27,  1881— Applied 
upon  pear  tree  by  the  spray  atomizer.  August 
2d — Result  same  as  the  preceding.  October  14, 
1882— This  tree  did  not  suffer  from  the  effects 
of  the  <  ^plication,  but  this  season  has  made  a 
vigorous  growth  of  new  wood  quite  clean  from 
scale.  The  foregoing  applications  of  kerosene 
and  gasoline  were  made  in  full  strength. 

Whale  Oil  Soap  and  Sulphur. 

No.  21.  Whale  oil  soap  and  sulphur  mixt- 
ure 1  lb.,  water  1  gal.  June  23,  1881— Ap- 
plied  by  spray  over  pear  tree,  covering  foliage 
and  fruit  thoroughly.  July  23d — Scale  killed; 
tree  gaining  in  health;  green  layer  of  bark  be- 
ing restored;  fruit  greatly  improved  in  appear- 
ance. August  2,  1881 — Tree  still  improving, 
also  fruit.  April  28,  1882— Tree  very  healthy 
and  appears  clean  from  scale;  green  layer  of 
bark  being  fully  restored,  and  parts  of  the  tree 
that  were  nearly  killed  by  the  scale  are  form- 
ing new  bark  rapidly;  the  tree  has  a  very  fine 
top  of  new  growth.  October  14,  1882— The 
tree  has  grown  very  thriftily  through  the  sea- 
son and  the  wood  is  all  very  healthy;  some 
scale  are  found  upon  the  tree,  however.  These 
trees  are  in  an  orchard  badly  infested,  and  it  is 
to  be  expected  that  the  insects  will  return. 
This  wash  is  an  effectual  summer  wash,  and 
where  there  is  any  scale  present  should  be  used 
in  the  strength  here  given,  as  a  wash  of  one- 
half  the  strength  has  proven  ineffectual. 

Soft  Soap  and  Sulphur. 

No.  22.  Soft  soap,  one  pound;  sulphur,  one 
pound;  tobacco,  one  pound;  water,  three  gal- 
lons. July  5,  1881 — Applied  upon  two  trees  by 
spray,  covering  trees,  foliage  and  fruit  thor- 
oughly. July  23,  1881— Seemed  quite  effectual 
at  the  time;  many  scale  destroyed,  but  not  all; 
trees,  not  affected  by  the  wash;  fruit  improved  in 
appearance.  Subsequent  observations,  however, 
showed  that  but  little  was  accomplished  in 
destroying  the  scale.  October  14,  1882— This 
tree  shows  an  abundance  of  live  scale  in  all 
stages  of  growth.  This  wash  was  used  with  good 
effect  in  another  orchard,  June  1,  1881,  on  a 


Fellenberg  prune  tree,  clearing  it  from  scale, 
which,  up  to  this  time,  have  not  returned. 

No.  23.  Soft  soap,  one  pound;  sulphur,  1 
pound;  water,  three  gallons. 

No.  24.  Soft  soap,  1  pound;  water,  3  gallons; 
The  two  washes  named  above  were  applied 
June  23,  1881,  and  with  no  effect,  neither 
has  it  shown  any  result  this  season. 

Whale  Oil  Mixture. 

No.  25.  Whale  oil,  one  pint;  kerosene,  one 
pint;  borax,  one  ounce;  water,  one  gallon.  June 
23,  1881 — Applied  by  spray  to  a  pear  tree  at 
the  different  dates  in  1881;  the  effect  has  been 
observed ;  it  has  been  apparent  that  the  oil  is 
decidedly  injurious  to  the  tree,  applied  in  this 
manner  or  at  this  time;  it  is  therefore  not 
recommended.  Applied  to  another  tree  in  one- 
fifth  the  strength  above  given;  it  has  no  effect 
upon  either  scale  or  tree.  April  25,  1882— The 
tree  first  treated  is  nearly  dead;  but,  however, 
having  the  top  cut  off,  new  wood  is  coming 
along;  scale  appears  to  be  destroyed.  October 
14,  1882— The  old  wood  is  dead;  the  sickly 
growth  of  new  wood  springing  out  from  the 
lower  portion  of  the  tree  shows  some  scale. 

Carbolic  Acid. 

No.  26.  Carbolic  acid,  three  ozs.j  water,  two  gal- 
lons. June  23,  1881 — Applied  by  spray  upon  a 
pear  tree  badly  infested  with  scale.  June  27, 
1881— Failed  entirely.  This  tree  afforded  a  con- 
stant succession  of  insects  in  all  stages  of  devel- 
opment, both  male  and  female.  From  it  some 
of  our  most  interesting  studies  were  made;  we 
repeat  it  as  it  appeared  at  each  visit  on  that 
date  (June  27,  1881);  we  found  the  male  insect 
under  its  scale  partially  developed,  with  wing 
pads,  but  wings  not  yet  out.  July  2d—  Found 
plenty  of  winged  males  of  the  second  brood  fly- 
ing and  crawling  about.  July  23d— Tree  was 
covered  with  young  female  scale  insects  of  the 
second  brood  crawling,  and  with  a  few  of  them 
just  located  and  commencing  to  be 
covered  with  their  scale.  July  25th — A 
few  of  the  winged  male  still  found; 
bark  scraped  clean  on  this  date  was  in  two 
days  covered  with  young  scale  and  with  a  slight 
formation  of  scale  over  them.  Aug.  2d — Tree 
entirely  covered  with  young  scale  on  this  date; 
two  or  three  winged  males  were  found.  April 
25,  1882— Tree  almost  dead  from  effects  of 
scale;  top  dead  and  removed  and  a  few  feeble 
shoots  coming  forth.  October  14,  1882— Shoots 
have  grown  from  the  trnnk  of  the  tree  to  some 
extent,  but  the  whole  having  been  so  seriously 
infested  the  tree  is  considered  worthless. 

The  entire  orchard  in  which  these  trees  are 
situated,  other  than  the  ones  experimented  on, 
from  8  to  26  were  washed  this  past  winter  with 
a  very  low  grade  of  coal  oil  called  "tree  wash;" 
the  result  is  not  satisfactory;  the  owner 
tells  mej(0ctober  14,  1882)  that  he  is  satisfied 
that  the  oil  has  seriously  injured  his  trees. 

San  Jose.  October  25.  1882. 

Experiments  with  Steam. 

It  was  at  one  time  thought  that  steam  might 
be  effectually  applied  for  the  extermination  of 
insect  pests  upon  trees.  In  the  summer  of  1881 
a  test  of  this  agent  was  made  in  an  orchard  near 
San  Jose.  A  large  tent  was  made  to  hang  upon 
a  frame,  which  could  be  run  on  either  side  of. 


and  overhanging  the  tree;  the  tent  then  being 
dropped,  the  tree  was  entirely  enclosed  in  an 
air-tight  bag,  into  which  the  steam  and  other 
ingredients  were  forced,  and  left  to  act  upon 
the  tree  and  insects  as  long  as  was  thought  nec- 
essary. 

Horticultural  Commissioner  D.  C.  Vestal  and 
myself  carefully  noted  the  experiments  made 
and  placed  the  results  upon  record.  These  ex 
periments  are  also  numbered  for  convenience  in 
describing. 

No.  1.  Sept.  8,  1881.  An  apple  tree  infested 
with  scale  insect,  wooiy  aphis  and  other  pests, 
was  covered  by  the  tent, under  which  was  hung 
upon  the  tree  cloths  saturated  with  bi-sulphide 
carbon,  one-half  pound.  It  was  thus  left  for 
three- fourths  of  an  hour,  and  then  the  tent  was 
removed.  Result,  apparently  of  no  effect.  The 
woolly  aphis  was  not  injured,  but  found  crawl- 
ing about.  The  red  spider  was  found  crawling 
about;  also  a  small  caterpillar  was  observed 
unharmed.  The  scale  insects  were  not  affected 
in  any  ^ay,  so  far  as  could  be  observed.  Sept. 
12,  1881— Examination  made  on  this  date 
showed  that  no  effect  had  been  made  by  the  ap- 
plication upon  any  of  the  insects  mentioned  as 
infesting  this  tree.  Mr.  J.  H.  Wheeler,  the 
maker  or  the  bi  sulphide  carbon,  thought  that 
the  agent  had  not  been  properly  brought  into 
contact  with  the  insects,  and  for  that  reason 
failed  to  destroy  them. 

No.  2.  A  pear  tree  was  treated  with  steam 
forced  under  the  tent  covering  the  tree.  The 
temperature  was  raised  to  165°,  and  maintained 
for  10  minutes.  Observations  immediately  af- 
terwards showed  that  the  foliage  of  the  tree 
and  the  young  wood  of  the  tree  waa  destroyed. 
Everything  was  cooked  thoroughly.  Septem- 
ber l2th — The  tree  and  the  scale  were  both 
killed. 

No.  3.  An  apple  tree  was  treated  in  the 
same  manner,  with  steam  at  140°, 
for  three  minutes,  and  afterwards  with 
sulphur  fumes  (caused  by  putting  two 
handsful  of  sulphur  upon  live  coals)  for  five 
minutes.  The  result  showed  that  the  tree 
did  not  appear  quite  so  much  injured  at  this 
time  as  the  preceding  tree  at  first  showed, 
but  as  seen  on  September  12  bh  the  effect  was 
the  same.  The  scale  was  killed,  and  also  the 
entire  tree,  except  the  oldest  part  of  the  trunk. 

No,  4.  Apple  tree  steamed  for  five  minutes 
at  140°;  dri^d  for  five  minutes,  and  then  fumed 
with  sulphur  for  five  minutes,  llssult  the  same 
as  the  preceding. 

No.  5.  Apple  tree  moderately  covered  with 
scale  and  woolly  aphis.  Steam  applied  with 
which  had  previously  been  mixed  three  gallons 
of  kerosene,  pumped  into  the  boiler  of  a  thresh- 
ing engine.  This  application  was  made  at  110° 
and  maintained  for  four  minutes.  September 
12th — No  effect  was  perceptible  upon  the  tree, 
except  that  the  foliage  was  somewhat  injured. 
The  scale  insect  was  not  killed  or  even  injured. 
The  woolly  aphis  was  found  alive  and  uninjured. 

No.  6.  Steam  and  coal  oil  applied  tour  min- 
utes at  140°.  September  12— Tree  pretty  nearly 
killed.  Only  the  oldest  wood  alive — all  new 
wood  and  buds  killed. 

No.  7.  Steam  and  coal  oil  for  six  minutes  at 
130°;  No.  8,  same  for  six  minutes  at  150°;  No. 
9,  same  for  12  minutes  at  120°  to  130°.  This 
tree  was  steamed  four  minutes,  and  then,  after 


an  interval  of  six  minutes,  was  steamed  two 
minutes  more.  September  12th — The  result 
upon  these  trees  was  the  same.  The  trees  were 
all  destroyed  excepting  the  trunk  and  oldest 
wood. 

From  these  experiments  it  will  be  seen  that 
steam  cannot  be  applied  in  such  manner  and  at 
a  temperature  sufficiently  high  to  destroy  the 
insects  without,  at  the  same  time,  destroying 
the  tree. 

During  the  season  of  1881  strong  efforts  were 
made  to  introduce  the  use  of 

Various  Patented  Mixtures, 

Which  were  claimed  to  have  great  merit  in 
destroying  the  scale  insect.  One  of  these  was 
to  be  used  by  simply  spreading  it  on  the  trunk 
of  the  tree,  which  application  it  was  stated 
would,  through  the  poisoning  of  the  sap,  kill 
the  insects.  This,  as  well  as  others  of  a  like 
nature,  were  given  careful  consideration  and 
tested,  and  resulted  in  entire  failure. 

Another  method,  which  was  persistently 
forced  upon  the  public,  was  that  of  boring  into 
the  trunk  of  the  tree  to  the  centre,  and  filling 
the  auger  hole  with  the  so-called  care.  A  care- 
ful investigation  of  many  trees  so  treated  was 
made  by  Mr.  Mathew  Cooke,  Mr.  D.  C.  Vestal 
and  myself,  for  the  purpose  of  determining  the 
actual  effects,  if  any,  of  this  treatment.  Oct. 
17,  '81,  we  visited  the  orchard  of  one  person, 
who  had  allowed  his  name  to  be  used  in  recom- 
mending this  exterminator,  and  first  Cammed 
two  pear  trees  bored  and  the  holes  filled  with 
the  preparation.  These  trees  were  found  to  be 
covered  with  live  scale  insects  in  all  stages  of 
development,  and  showing  no  signs  of  injury. 
The  young  female  insects  were  found  crawling 
about  the  trees  in  great  numbers.  The  wood, 
the  seasons  growth,  was  covered  with  scale. 
An  apple  tree,  the  trunk  and  large  limbs  of 
which  had  been  washed  the  previous  winter 
with  strong  lye,  showed  that  the  scale  which 
completely  covered  it  when  the  lye  was  ap- 
plied were  entirely  destroyed  where  the  wash 
had  reached,  but  on  the  smaller  wood  which 
had  not  been  washed  with  the  lye  the  scale  was 
found  alive.  This  tree  had  also  been  bored  and 
treated  with  the  application  referred  to,  and 
which  had  no  effect  whatever.  On  the  trunk 
of  this  tree,  where  the  lye  had  been  applied, 
the  green  layer  of  bark  was  found  replacing  the 
old,  which  had  nearly  been  destroyed  by  the 
scale.  At  another  place  we  examined  a  pear 
tree  which  had  been  bored  and  treated  with 
this  preparation.  This  tree  was  in  no  manner 
whatever  affected  by  this  so-called  remedy,  but 
was  completely  covered  with  scale  insects  in 
every  stage.  We  found  the  young  females 
crawling  about,  and  on  this  tree  was  found  the 
male  scale  in  the  first  pupa  stage  of  develop- 
ment for  the  third  winged  brood,  and  also  on 
this  tree  was  discovered  the  perfect  winged 
male  of  the  third  brood.  In  no  case  has  the 
slightest  good  resulted  from  these  secret  and 
patented  preparations.  We  have  treated  this 
subject  thus  fully  because,  to  our  knowledge, 
prominent  and  careful  horticulturists  have  been 
induced  to  purchase  these  things  at  an  exhor- 
bitant  charge. 

The  treatment  of  trees  by 

Crude  Petroleum 
And  its  different  products  has   been  thoroughly 


cited  to   show   the.  effrc^e/"  of  lye    as   an  in- 
secticide, &?t  vsufri.)iefc.'t  fact's  'ate  staled. 

How  the  Insects  are  Spread. 

Attention  must  be  called  to  the  means  of 
spreading  this  serious  pest,  the  aspidiotus  per- 
niciosus.  The  system  of  "return  boxes,"  and 
packages  of  any  character,  is  known  to  be  per- 
nicious and  a  fruitful  source  of  the  spread  of 
all  kinds  of  noxious  insects,  which,  either  as 
insects,  eggs  or  larvre,  are  fastened  to  them  and 
taken  into  the  orchard,  to  be  developed  in  due 
time,  and  then  to  spread  devastation  to  every- 
thing attacked.  Indeed,  to  me,  so  obnoxious  is 
the  return  box  that  I  will  not  permit  one  to  be 
brought  into  the  orchard  or  on  the  premises.  I 
prefer  to  pay  the  cost  of  new  boxes,  and  give 
them  with  the  fruit  sold.  As  the  female  insect 
has  no  wings,  she  can,  of  course,  only  be  spread 
about  by  becoming  attached  to  something  by 
which  she  is  carried  to  different  localities,  and 
by  crawling  about  during  the  short  period  after 
hatching  before  becoming  fixed  for  life. 

Birds  will  carry  them  most  frequently  about 
an  orchard,  and  it  is  thought  that  one  source  of 
danger  is  little  regarded,  viz :  carrying  them 
about  on  one's  clothing  by  brushing  against  in- 
fested trees. 

If  boxes  or  packages  are  returned,  they  should 
be  disinfected  as  soon  as  received  by  dipping  in 
boiling  water,  to  which  is  added  not  less  than 
one  pound  of  potash  to  25  gallons  of  the  water 
used. 

The  nursery  trees  sent  over  the  State  have 
been  the  means  of  spreading  the  scale  exten- 
sively, and  while  nurserymen  are  anxious  to 
make  sale  of  their  trees  they  must  take  every 
precaution  to  see  that  their  patrons  do  not  suf- 
fer by  neglect  to  first  destroy  the  scale,  which 
may  be  done  by  dipping  the  trees  in  a  solution 
of  concentrated  lye  of  1  K>,  to  2  gallons  of 
water.  I  am  glad  to  say  that  most  nurserymen 
are  desirous  to  do  all  in  their  power  to  destroy 
the  scale. 

Among  other  means  of  preventing  the  spread 
of  scale,  thorough  and  constant  cultivation  of 
an  orchard  should  be  kept  up,  and  one  promi- 
nent difficulty  in  the  way  of  eradicating  the 
scale  I  believe  to  be  the  practice  so  prevalent 
of  growing  other  small  crops  in  the  orchard  be- 
tween the  trees. 

It  cannot  be  too  strongly  impressed  upon  the 
mind  of  every  owner  of  an  orchard  that  he  must 
personally  watch  his  orchard  and  exercise  such 
constant  supervision  that  no  infested  tree  shall 
escape  observation,  and,  when  found,  the  proper 
remedy  at  once  be  applied.  In  the  orchard  re- 
ferred to  where  chance  trees  have  been  found 
infested,  no  other  course  would  have  saved  me 
from  the  overwhelming  spread  of  the  scale. 

The  experiments  of  1881  and  the  subsequent 
use  of  lye  in  instances  mentioned,  indicate  the 
remedy.  This  should  always  be  used  when  the 
tree  is  dormant,  and  when  the  foliage  has  dis- 
appeared from  the  trees.  In  our  climate  that 
time  is  the  winter,  and  at  any  time  before  the 
trees  put  forth  their  buds. 


Applying  the  Lye. 

The  strength  of  lye  should  be  one  It),  to  one 
gallon  water  where  trees  are  infested  with 
scale.  Where  it  is  only  desired  to  cleanse  the 
tree  from  moss  one  K>.  to  three  or  four  gallons 
of  water  is  sufficient.  The  best  method  of  ap- 
plying  the  concentrated  lye  is  by  dissolving  in 
boiling  water,  and  throwing  it  upon  the  trees 
with  a  force  pump  through  40  or  50  ft.  of  «•»- 
jHjl  one-half  inch  rubber  hose,  to  which  is  at- 
tached a  nozzle,  having  for  its  opening  a  simple 
straight  slit,  very  narrow  in  width,  and 
one-sixteenth  to  one- eighth  of  an  inch  long. 
The  best  spray  tip  yet  devised  is  that  made  at 
San  Jose,  called  the  Merigot  Spray  Nozzle. 
The  pumps  most  used  for  this  purpose  are  the 
Gould  pump  and  the  Merigot  pump.  The  latter 
is  made  at  San  Jose,  and  is  cheaper  than  the 
Gould  pump.  Great  care  should  be  taken  to 
cover  the  tree  entirely  with  the  solution  of  lye, 
as  upon  its  thorough  application  depends  its 
success. 

One  of  the  greatest  difficulties  in  the  use  of 
strong  materials  is  from  the  spray  falling  upon 
the  person  of  the  operator  and  burning  and 
injuring  the  skin.  la  order  to  overcome 
this  obstacle,  I  have  devised  a  simple  "exten- 
sion nozzle"  of  slight  cost  which  is  very  light 
and  which  may  be  made  of  any  length  desired, 
say  from  four  to  15  ft.,  or  even  longer.  By  the 
use  of  this  extension  it  is"  perfectly  easy  to  reach 
and  spray  any  orchard  tree  without  danger  and 
discomfort.  The  cost  of  materials  and  appa- 
ratus may  be  given  as  follows: 

The  Gould  pump  costsabout  $10  without  acces- 
saries. The  Merigot  pump  $12.  The  suction  hose 
and  the  long  hose  will  cost  according  to  quality 
used,  from  15  cents  to  25  cents  per  foot. 

The  Merigot  spray  tip,  if  purchased  alone, 
$1.50.  If  bought  with  pump,  the  pump  and 
spray  $13.  The  bamboo  extension  with  globe 
valve  seven  ft.  long  $2.75.  All  excess  in  length 
over  seven  ft.  25  cents  per  foot.  The  concen- 
trated lye,  of  the  American  Lye  Co.  in  one-It) 
cans  by  the  case  of  48  R>3.,  $3  50  per  case. 
English  caustic  soda  in  GOO  pouod  drums,  $33  to 
$35  per  drum.  The  whale  oil  soap  and  sulphur 
mixture  called  the  "Codlin  Moth  Wash"  is 
manufactured  in  San  Francisco  and  the  price 
can  be  obtained  by  inquiring  of  Messrs  Allyne 
&  White. 

In  conclusion  I  will  give  the  analysis  made 
v  Prof.  Hilgard,  of  the  State  University,  of  a 
sample  can  of  American  Lye  Co.  concentrated 
lye.  The  can  sent  I  took  from  a  lot  I  had  been 
using,  and  is  supposed  to  be  a  fair  sample  of  the 
manufacture.  The  analysis  is  as  follows: 


Caustic  potash 

Caustic  soda  and  carbonate  of  soda 


8.3 
91.7 


100.0 


With  this  I  submit  my  report,  expressing 
my  firm  conviction  that  ere  long  we  shall  be 
freed  from  the  ravages  of  one  of  the  most 
dreaded  pests  known  to  horticulturists. 


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